Currently used net-shape additive manufacturing techniques build alloy components layer by layer by melting powders or wires using a laser or electron beam power source. However, although very manipulative, these power sources are rather expensive and require high levels of maintenance and safety procedures. They are also mainly suited to manufacturing of small scale components because of the small spot size of the energy beam that is normally used for greater accuracy during the build process. Potential use of these methods for medium and large sized components would take long processing times and therefore are prohibitively expensive. Furthermore, these methods are not suitable for obtaining low surface roughness, and finishing machining is therefore normally required for most applications. Larger scale additive manufacturing processes use plasma arcs to melt the input consumable wire feedstock similar to welding operations. These methods produce pre-forms, i.e. crudely shaped billets that need to be subsequently machined to the component shape.
For use in space, these methods would be even more disadvantageous as these power sources for additive manufacturing are heavy and would significantly increase the payload particularly in terms of battery energy storage. Therefore, for space applications it is normally necessary to bring a whole range of tools and parts that might be needed, and this also increases the payload.
Hence, an improved additive manufacturing method would be advantageous, and in particular a more efficient and/or less expensive method would be advantageous.